0,2

(PARI) {a(n)=local(A=matrix(1, 1), B); A[1, 1]=1; for(m=2, n+1, B=matrix(m, m); for(i=1, m, for(j=1, i, if(j==i, B[i, j]=j, if(j==1, B[i, j]=(A^2)[i-1, 1], B[i, j]=(A^2)[i-1, j])); )); A=B); return(sum(k=0, n, A[n+1, k+1]/(k+1)))}

Cf. A106208.

Sequence in context: A112317 A089459 A027882 this_sequence A003266 A097385 A066068

Adjacent sequences: A106206 A106207 A106208 this_sequence A106210 A106211 A106212

nonn

Paul D. Hanna (pauldhanna(AT)juno.com), May 01 2005